Aiming at the disadvantage of existing equipment maintenance accessibility evaluation method, this paper studied the project of equipment maintenance accessibility evaluation. a method of equipment maintenance accessibility evaluation in the virtual environment is put forward based on Matrices Permanent and index correlation degree , at last an example is given. It is significant for developing maintainability verification and increasing Equipment Maintainability in the course of equipment digital mock-up designing.

Aiming to lack for the verification method of equipment maintainability quantitative requirements, this paper researched the verification method of average replacement time through virtual simulation technology, and proposed the mathematical model of average replacement time, which can lay the foundation for maintainability virtual verification.

Aiming at the disadvantage of existing equipment MTTR demonstration method, this paper studied the project of equipment maintainability demonstration Based on Virtual Simulation, and put forward a method of equipment MTTR demonstration in the virtual environment, at last power system of equipment is verified as an example. It is significant for developing maintainability demonstration and increasing Equipment maintainability in the course of equipment digital mock-up designing.

Polyethylene Glycol Oleate was synthesized by esterification of polyethylene glycol and Oil acid using DMAP as a catalyst. The double bonds of the product in the core of micelles were cross-linked by the initiation of (NH4)2S2O8 during the micelles formed. Applications of the noncross-linked and cross-linked polyethylene glycol oleate in drug delivery were studied, which indicates that drug efficiency decreased after micelles were core cross-linked, but release rate of MTX from core cross-linked micelles seems slower than that from noncross-linked micelles.

Aiming at the disadvantage of existing materiel maintainability quantitative requirements demonstration method, this paper studied the project of the materiel maintainability qualitative requirement demonstration Based on virtual simulation, in order to determine the materiel maintainability qualitative requirement, the accessibility and visibility as an example to illustrate the virtual demonstration method. It is significant for developing maintainability demonstration and increasing materiel maintainability in the course of materiel digital mock-up designing.